The Charisma Engine - The Charisma Engine is Radeon 7500’s transform, clipping and lighting engine (also known as a geometry engine).  The Charisma Engine will allow the Radeon  7500 to perform the complex transformations, clipping and lighting calculations demanded by the latest 3D games.  As well, the Radeon  7500 supports such DirectX 8.0 features as Keyframe Interpolation and 4-Matrix Vertex Skinning bringing 3D characters to a new visual level of realism.

The Pixel Tapestry Architecture - The Pixel Tapestry Architecture is essentially the Radeon 7500’s powerful rendering engine. Radeon 7500 is one of the only graphic cards in its class capable of processing up to three independent texture units in each rendering pipeline. As a result, the application of up to three textures per pipeline allows for increased realism to 3D characters and environments while maintaining a high performance level.

The diagram below shows how objects can be rendered more realistically with the application of multiple textures.

Furthermore, advanced rendering/texturing technologies are supported with the Pixel Tapestry Architecture.  The Radeon  7500 supports 3 types of bump mapping (Emboss, Dot Product 3, and Environment Bump Mapping) and 3 types of environment mapping (spherical, dual-paraboloid, and cubic environment mapping).  The result is that the Radeon  7500 can achieve the rendering of incredibly authentic-looking 3D characters and environments.

The image below shows the Environment Mapped Bump Mapping test that we can recognize from 3D Mark 2001. This is supported in the hardware of Radeon 7500. Environment Mapped Bump Mapping is especially useful for objects that are shiny, glossy or reflective and this is one of the major strengths of this technique.  Emboss and Dot Product 3 are not techniques, which work well with shiny/glossy objects.

One can view the realistic effects of a complex multi-textured environment with some of the latest games utilizing three textures per pixel and is one of the advanced 3D games that can take advantage of the Pixel Tapestry Architecture.  Looking at the next image, one can view the realism added to the picture of the landscape with the use of three textures.  Pixel Tapestry Architecture is capable of processing this next level of realism in games by applying all three textures per pixel in a single clock cycle.

HyperZ Technology - ATI's Radeon 7500 chip takes an smart approach to the memory bandwidth limitation issue. Innovative HYPERZ technology improves memory bandwidth efficiency without the added cost of exotic embedded or proprietary memory technologies. By attacking this key bottleneck, the Radeon 7500 can reach new heights in 3D performance. The speed and type of memory accompanying a graphics chip places upper bounds on the fill rate it can achieve. With 230MHz DDR memory, the physical memory alone can transfer data at up to 7.4GB/sec. With HYPERZ technology, the effective memory bandwidth is boosted by 20% and effectively transfers up to 8.8GB/sec giving the Radeon 7500 plenty of 'breathing space'.

Basically this covers the Radeon 7500 silicon technology. It's a very decent and fast silicon however missing some newer functions that it's big brother the Radeon 8500 carries and basically renders this card to a 'DirectX 7' 3D graphics card as it will miss out on newer DirectX 8 and 9 features.